Electronic devices such as computer games and cellular phones are becoming smaller and smaller. As a result, elements such as inductors mounted in such an electronic device also need to be smaller. One example of a known inductor mounted in such an electronic device uses a winding coil. For example, an inductor that uses a winding coil may be mounted in a power supply circuit of an electronic device (see Japanese Laid-Open Patent Publication No. 2003-168610).